Apparatus and method for controlling roller rotation of laminator

ABSTRACT

There exist many problems that the film is wound on the heating roller or the pressing roller during operation of the laminator. Disclosed is an apparatus and method for controlling roller rotation in the laminator in order to resolve such problems, such that the film detecting sensor in the entrance side and the film detecting sensor in the exit side are provided in the front and back of the roller for normal operation of the laminator, so that if the film is not detected by the film detecting senor in the exit side after insertion of the laminating film is detected by the film detecting sensor in the entrance side, then the roller is rotated backward under judgment that the laminator does not normally operate.

TECHNICAL FIELD

The present invention relates to a laminator and more particularly to anapparatus and method for controlling roller rotation of a laminator,capable of automatically removing a film upon abnormal operation of thelaminator when the laminating film is wound on a roller, or film jam isgenerated in the inside of the laminator.

BACKGROUND ART

A laminator is an apparatus used for coating both sides of a plateshaped product using a film in order to improve durability of the plateshaped product such as a paper and a panel.

Generally, a laminator includes, as primary elements, a heating rollerfor applying heat on a laminating film upon coating; a pressing rollerfor making the films on both sides stuck on the product by applyingpressure on the heated laminating film; and a motor for applyingrotational force on the heating roller and the pressing roller.

Operation of the laminator will be described. After a film is insertedinto the laminator, heat is applied to the laminating film by theheating roller. The film on which heat is applied, changes into aflexible status where sticking is possibly performed, and pressure isapplied on that flexible film by the pressure roller, so that a pair ofthe laminating films is stuck on each other. At the moment, an adhesivecould be provided on a contact surface of the film so that adhesiveproperty may be improved.

But, in case that the temperature appropriate for thickness of thelaminating film is not properly adjusted or a small size laminating filmis used in such laminator, the heated laminating film is wound on theheating roller or the pressing roller and operation of the laminator isnot normally performed.

Also, in case that the film is not inserted in a correct angle but in atwisted angle when inserted into the laminator, a jam of the film isgenerated in the inside of the laminator and operation of the laminatoris not normally performed from time to time.

A method of a related art used for removing the laminating film from theinside of the laminator in such cases, will be described in thefollowing.

Firstly, a method for forcibly removing the film after stopping anddisassembling the laminator.

Secondly, a method for removing the film such that a dual-directionrotating motor is installed so that a user may manually adjustrotational direction of the motor in order to rotate backward theheating roller and the pressing roller in the inside of the laminatorwhen the film is wound in the inside of the laminator.

Thirdly, a method suggested in the Korean Utility Model Registration No.263043, in which a predetermined device for detecting thickness of thefilm piled up is installed on the outer periphery of the roller, so thatthe motor is automatically rotated backward for the film to be removedif the film is wound on the roller and reaches up to a predeterminedthickness.

According to the above first method, visiting of an expert is requiredto disassemble the laminator and the laminator should be assembled againafter the laminator is disassembled and the film is removed.

According to the second method, a user should continuously observewhether the film is normally inserted in or drawn out and shoulddirectly adjust operation of the laminator. Also, in case that much timelapses and the laminating film is deeply wound in the inside of thelaminator while a user does not observe the laminator upon coating job,the laminator machine itself including the roller might be destroyed.

According to the third method, winding of the film on the roller couldbe detected if and only if the film is continuously wound on the rollerand reaches up to a considerable thickness. Therefore, abnormaloperation of the laminator could not be detected until malfunctionalready occurs for a considerable period of time. Also, a predetermineddevice for detecting the thickness of the piled up film should beinstalled on all the rollers where there exist possibility thatmalfunction occurs, so that this method could not be applied to thelaminator on which the rollers are formed in multi-levels. Also, due toinaccuracy of mechanical detection of the film thickness, reliabilitycould not be secured in detecting malfunction of the laminator.

DISCLOSURE OF INVENTION

To solve the above-indicated problems, it is, therefore, an object ofthe present invention to provide an apparatus and method for controllingroller rotation of a laminator, which is convenient and reliable.

An apparatus for controlling roller rotation of a laminator according tothe present invention, includes: rollers installed in even numbers, forapplying heat and pressure in order to perform coating using alaminating film; a film detecting sensor in an entrance side, formed inthe front side of the roller with respect to the progressing directionof the laminating film, for detecting whether the laminating film isinserted or not; a film detecting sensor in an exit side, formed in therear side of the roller, for detecting whether the laminating film isdrawn out or not; a dual-direction rotating motor for rotating theroller forward or backward depending on a detecting signal from the filmdetecting sensors in the entrance side and the exit side; amicroprocessor for receiving a detecting signal from the sensor andtransmitting a controlling signal to the dual-direction rotating motor;and a power transferring unit for transferring power from thedual-direction motor to the roller.

A method for controlling roller rotation of a laminator according to thepresent invention, includes the steps of: counting time from the momentthat insertion of a laminating film is detected by a film detectingsensor in an entrance side after the laminating film is inserted intothe laminator; detecting, at a film detecting sensor in an exit side,the laminating film after waiting time T1 that is necessary for normallaminating operation lapses; judging that normal laminating is performedif the laminating film is detected before the waiting time T1 lapses,and removing the film by rotating backward the roller for apredetermined period of time T2 under the judgment that normallaminating is not performed if the laminating film is not detected evenafter the waiting time T1 lapses.

BRIEF DESCRIPTION OF INVENTION

The above objects, features and advantages of the present invention willbecome more apparent from the following detailed description when takenin conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of an appearance of a laminator adopting anapparatus for controlling roller rotation of a laminator according tothe present invention;

FIG. 2 is a perspective view of a laminator whose upper cover isseparated in a laminator adopting an apparatus for controlling rollerrotation according to the present invention;

FIG. 3 is an exploded, perspective view of a crucial part of a laminatoradopting an apparatus for controlling roller rotation according to thepresent invention;

FIG. 4 is a schematic, cross-sectional view taken along line A-A′ inFIG. 2, illustrating operation of an apparatus for controlling rollerrotation of a laminator according to the present invention; and

FIG. 5 is a flowchart illustrating a method for controlling rollerrotation of a laminator according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

A preferred embodiment of the present invention will now be describedwith reference to the accompanying drawings. The matters defined in thedescription such as a detailed construction and elements are nothing butthe ones provided to assist in a comprehensive understanding of theinvention. Thus, it is apparent that the present invention can becarried out without those defined matters. Also, well-known functions orconstructions are not described in detail since they would obscure theinvention in unnecessary detail.

FIG. 1 is a perspective view of an appearance of a laminator adopting anapparatus for controlling roller rotation of a laminator according tothe present invention.

Referring to FIG. 1, an appearance of the present invention includes anupper cover 7 and a lower cover 8 forming an appearance of thelaminator, and the upper cover 7 includes: a power switch 1 forcontrolling on/off of the laminator, a standby indicating lamp 2 forindicating an operation standby status of a laminator; a powerindicating lamp 3 for indicating a status that power of the laminator isturned on; a temperature adjusting member 4 for properly adjustingtemperature depending on thickness of a laminating film; and a receivingmember 5 formed lengthwise in the front side, for receiving thelaminating film.

Also, a drawing member 6 through which a coated laminating film is drawnout is provided in the rear side of the upper cover 7, and a pluralityof heat emitting members 9 for emitting heat from the inside of thelaminator, is provided on the front side of the upper cover 7.

Mores specifically, for the power switch 1, a switching means of threesteps for controlling status of forward rotation, backward rotation, andoff status of the laminator, is used. With such construction, forwardand backward rotations of the laminator could be controlled by directoperation of a user.

Also, the heat emitting member 9 has a plurality of slits in a long holeshape, so that heat generated from the inside of the laminator may beswiftly emitted to the outside.

Also, for the temperature adjusting member 4, a rotary switch turneddirectly by a user is used, so that appropriate temperature may beadjusted.

Referring to FIG. 1, operation of the laminator according to the presentinvention will be briefly described. In case that a user intends tooperate the laminator, the power switch 1 is set to on-status where theroller is rotated forward, so that the roller may be rotated. Then,temperature of the temperature adjusting member 4 is appropriatelyselected depending on thickness of the laminating film, so that theheating roller in the inside of the laminator may be heated to anappropriate temperature. At the moment, the standby indicating lamp 2keeps blinking until the heating roller reaches a temperature rangeappropriate for performance of laminating while the heating roller isheated, so that a user may recognize the standby status of thelaminator, namely, the status that the laminator is not yet prepared forlaminating operation.

If the heating roller reaches an appropriate temperature, the standbylamp 2 stops blinking and maintains lighted-up status, so that a usermay recognize that the heating roller is prepared for laminatingoperation and perform laminating job.

In the meantime, in case that a user recognizes that the film is caughtin the inside of the laminator, or the film is wound on the roller, auser could make the film drawn out through the receiving member 5 bydirectly controlling the power switch 1 in order to get the roller to berotated backward.

Rest part not described in the foregoing will be described in moredetail in the following.

FIG. 2 is a perspective view of a laminator whose upper cover isseparated in a laminator adopting an apparatus for controlling rollerrotation according to the present invention.

Referring to FIG. 2, the laminator of the present invention includes: acontrolling substrate 30 in which a temperature adjusting member 4, apower switch 1, a standby indicating lamp 2, a power indicating lamp 3are connected by a predetermined wiring so that a series of operation bythe laminator may be performed; a heating roller (not shown) formed upand down in pairs, for applying heat on the laminating film; a pressingroller 35 formed in the rear side of the heating roller, for pressingthe laminating film; a dual-direction rotating motor 20 for applyingrotational force on the heating roller 36 and the pressing roller 35; apower transferring unit 25 for transferring power of the dual-directionrotating motor 20 to the heating roller 36 and the pressing roller 35.Also, a heating cover 39 for safe performance of job is additionallyprovided on the outer side of the heating roller.

More specifically, the power transferring unit 25 has a plurality ofgears for transferring torque of the dual-direction rotating motor 20.But, construction for power transfer is not necessarily limited to gearsand a person skilled in the art would easily think of various powertransferring mechanism such as a belt, a sprocket.

Particularly, a film detecting sensor 10 in an entrance side, fordetecting insertion status of the laminating film to be inserted, isprovided in the front of the heating roller, and a film detecting sensor15 in an exit side, through which the laminating completed film is drawnout, is provided in the rear side of the pressing roller 35.

Also, for the film detecting sensor 10 in the entrance side and the filmdetecting sensor 15 in the exit side, a member for simultaneouslyemitting and receiving light is used, so that existence of the film isdetected and insertion and drawing out of the film are detected if lightemitted from a light emitting unit of the sensor is reflected from thefilm and received to a light receiving unit of the sensor. Here, for thelight used for the sensors 10 and 15, an ultraviolet ray is used forstable operation of the machine.

Also, a microprocessor is mounted on the controlling substrate 30, forcontrolling the operation of the laminator on the whole. A plurality ofentering lines connected to parts such as the sensors 10 and 15, thepower switch 1, is connected to the controlling substrate 30 so thatoperation of the laminator may be stably performed.

FIG. 3 is an exploded, perspective view of a crucial part of a laminatoradopting an apparatus for controlling roller rotation according to thepresent invention.

Referring to FIG. 3, a heat applying unit 37 for applying heat on theheating roller 36, and the heating cover 39 formed on the upper side ofthe heat applying unit 37, for stable operation of the machine, areprovided on the outer side of the heating roller 36.

The film detecting sensor 10 in the entrance side is fixed by a sensorfixing panel 11, and the sensor fixing panel 11 is settled down in itsboth ends on the boss formed on the inner lower, side of the lower cover8. At the moment, the light emitting unit and the light receiving unitof the film detecting sensor 10 in the entrance side are put on a holeformed on the central portion of the sensor fixing panel 11, so thatprojection and incidence of light may not be disturbed.

But, for the film detecting sensor 10 in the entrance side, any memberwhatsoever may be used as far as the member is formed in front of theheating roller 36, namely, the first roller, and detailed constructionand method in installing the member are not limited to those shown inthe drawing.

Also, the film detecting sensor 15 in the exit side is provided in therear side of the pressing roller 36, in order to detect whether thecoated film is normally drawn out or not. Also, the film detectingsensor 15 in the exit side is fixed by a sensor fixing unit 16 formed onthe back of the lower cover 8. But, for the film detecting sensor 15 inthe exit side, any member whatsoever may be used as far as the member isformed in the rear side of the pressing roller 35, namely, the finalroller, and detailed construction and method in installing the memberare not limited to the sensor fixing unit 16 shown in the drawing.

In the meantime, on the position adjacent to the heating roller 36,specifically on one side of the heat applying unit 37, a temperaturesensor 40 for detecting the temperature of the heating roller 36 isformed, so that the appropriate temperature of the heating roller 36 maybe known and coating of the laminating film may be swiftly performeddepending on the thickness.

More specifically, if a user designates an appropriate temperature forthe laminating film using the temperature adjusting member (refer toreference numeral 4 in FIG. 1), the temperature sensor 40 detects thetemperature of the heating roller 36, transferring the same to thecontrolling substrate 30 so that the heating roller 36 may be heated tothe designated temperature. The microprocessor of the controllingsubstrate 30 controls the power of the heat applying unit 37 and thestandby indicating lamp 2 depending on the temperature of thetemperature sensor 40, thereby controlling application of the power tothe heat applying unit 37 and the lighting of the standby indicatinglamp 2.

FIG. 4 is a schematic, cross-sectional view taken along line A-A′ inFIG. 2, illustrating operation of an apparatus for controlling rollerrotation of a laminator according to the present invention.

Referring to FIG. 4, an apparatus and method for controlling rollerrotation of a laminator according to the present invention will bedescribed in the following.

If the laminating film FL is inserted into the inside of the laminatorby a user after the temperature of the heating roller 36 reaches anappropriate temperature, the laminating film is detected by the filmdetecting sensor 10 in the entrance side. At the moment, a detectingsignal from the film detecting sensor 10 in the entrance side due toinsertion of the film, is transferred to the microprocessor formed inthe controlling substrate 30, so that time from the moment thatinsertion of the film is detected, is counted.

Then, when the film is drawn out after laminating is performed by theheating roller 36 and the pressing roller 35, the film detecting sensor15 in the exit side detects whether the film is drawn out or not, sothat normal performance of coating for laminating film could be checked.

But, in case that coating is not normally performed, the film is notdrawn out to the drawing member (refer to reference numeral 6 in FIG.1).

In that case, the film is not detected by the film detecting sensor 15in the exit side even when a predetermined time T1 lapses after the filmis detected by the film detecting sensor 10 in the entrance side,whereby the microprocessor of the controlling substrate 30 judges thatlaminating is not normally performed, controlling the rollers 35 and 36to rotate backward automatically.

In the meantime, according to many experiments, if the film is notdetected by the film detecting sensor 15 in the exit side even when 17second through 19 second lapses after the film is detected by the filmdetecting sensor 10 in the entrance side, then coating job is considerednot to be normally performed. In that case, the heating roller 35 and/orthe pressing roller 35 are automatically rotated backward so that thefilm may be drawn out to the receiving member (refer to referencenumeral 5 in FIG. 1). Preferably, time for which the rollers 35 and 36are rotated backward is about 18-19 second, which is sufficient for allthe films to be removed.

For cases that laminating is not normally performed, there may exist acase that the film is wound on the rollers 35 and 36, for the heatingroller 36 is not reached to the appropriate temperature depending on thethickness of the laminating film, and a case that an insertion angle ofthe laminating film is not correct, so that jam of the film isgenerated.

Also, for numbers of the heating roller 36 and the pressing roller 35proposed in FIG. 4, two rollers constituting one party are used, but thepresent invention is not limited to such tow rollers, and may be appliedto any case whatsoever as far as a plurality of rollers is formed inpairs, respectively. But, as far as the film detecting sensor 10 in theentrance side is provided in the front of the first roller and the filmdetecting sensor 15 in the exit side is provided in the back of thefinal roller, other elements may change to various shape whatsoever anddo not matter much.

In the meantime, another embodiment of an apparatus for controllingroller rotation of the laminator according to the present invention willbe described in the following.

Most of jam of the film or the case that the film is wound on therollers 35 and 36 in the laminator are generated in the heating roller36. Therefore, sensors are installed in the front and back of theheating roller 36 so that malfunction of the laminator may be moreswiftly eliminated.

More specifically, the film detecting sensor in the entrance side andthe film detecting sensor in 15 the exit side are installed in the frontand the back of the heating roller, respectively, so that whether thefilm is wound on the heating roller 36 is detected and malfunction ofthe laminator is more swiftly known, whereby malfunction of the machineand disorder thereof could be prevented. Also, in case that the filmdetecting sensors are installed in the front and back of the heatingroller 36, the waiting time after the film is detected by the filmdetecting sensor in the entrance side, and the time for reverse rotationof the roller for removing the film could be reduced to the half of thetime.

Preferably, the waiting time since the film is detected by the sensor inthe entrance side is in the range of about 8-10 second, and the time forwhich the heating roller 36 is rotated backward after the film is notdetected by the sensor in the exit side, is in the range of about 9-10second.

In the meantime, it is possible that the sensors are provided in thefront and the back of the heating roller 36 and also provided in thefront and the back of the pressing roller 35 according to a specificusage status of the product as well as the embodiment proposed above.With such construction, if the film is not detected at the back afterdetected by the sensor in the front of the rollers 35 and 36, it isjudged that laminating is not normally performed, so that the relevantroller is rotated in order to remove the film. Namely, generation of thefilm jam in the specific rollers 35 and 36 is detected, whereby the filmis swiftly and exactly removed.

But, upon removal of the laminating film, the rollers in the front sidewith respect to the roller on which the film is wound, should be allrotated backward, so that the film may be swiftly removed.

FIG. 5 is a flowchart illustrating a method for controlling rollerrotation of a laminator according to the present invention.

Referring to FIG. 5, a method for controlling roller rotation of thelaminator according to the present invention will be described in thefollowing. Firstly, the power supply is applied to the laminator (step101). If the power supply is applied, the motor and the roller arerotated forward, so that the standby step where laminating could beperformed, is prepared (step 102). At the moment, the rollers 35 and 36are always rotated so that transformation may not be generated in therollers 35 and 36 of a circular shape while the power supply is appliedand heat is applied to the rollers. Also, while the motor is rotatedforward and heat is applied to the heating roller 36 so that thetemperature of the heating roller (refer to reference numeral 36 in FIG.4) is raised and heating is continuously performed, the standbyindicating lamp (refer to reference numeral 2 in FIG. 1) keeps blinkingso that a user may recognize that laminator is in a standby status (step103). After the temperature of the heating roller 36 reaches anappropriate temperature (step 104), blinking of the standby indicatinglamp 2 stops and a user inserts the laminating film into which materialto be coated is inserted, into the receiving member (refer to referencenumeral 5 in FIG. 1) (step 105). In the meantime, the step of rotatingforward the roller (step 102) and the step of heating the roller (step103) may be performed simultaneously without any priority in an order,or whether one step is performed prior to the other step does not mattermuch. But, if heat is applied and the rollers begin to be transformed,then the rollers 35 and 36 are rotated in order to preventtransformation generation in the rollers 35 and 36.

After the film is inserted, the film detecting sensor in the entranceside (refer to reference numeral 10 in FIG. 4) detects insertion of thelaminating film, and the time from the moment that the film is detected,is counted (step 106). The film inserted into the laminator experiencesheating and pressing, going through laminating process (step 107).

In the meantime, in case that laminating is not normally performed,namely, the film jam is generated or the film is wound on the rollers 35and 36 while coating is performed in the inside of the laminator, thefilm is not drawn out through the drawing member (refer to referencenumeral 6 in FIG. 1). Therefore, the film detecting sensor 15 in theexit side detects whether the film is present or not, determiningwhether laminator normally operates or not through detection results ofthe film detecting sensor in the exit side (step 108). Morespecifically, if the film is detected by the film detecting sensor 15 inthe exit side after the film is detected by the film detecting sensor 10in the entrance side and a predetermined period of time T1 lapses, thenit is judged that the laminator normally operates. But, if the film isnot detected by the film detecting sensor 15 in the exit side even afterthe film is detected by the film detecting sensor 10 in the entranceside and a predetermined period of time T1 lapses, then it is judgedthat the laminator does not normally operate, namely, the film is woundon the rollers 35 and 36, or the film is caught in the inside of thelaminator.

If the film is detected by the film detecting sensor 15 in the exit sidebefore a predetermined period of time T1 lapses, it is judged that thelaminator normally operate and a series of laminating process could benormally completed (step 109).

On the contrary, if the film is not is detected by the film detectingsensor 15 in the exit side even after the film is detected by the filmdetecting sensor 10 in the entrance side and a predetermined period oftime T1 lapses, then it is judged that the laminator does not normallyoperate and a series of step for removing film begins.

In the meantime, the predetermined period of waiting time T1 before thefilm is detected by the film detecting sensor in the exit side after thefilm is inserted to the side of the film detecting sensor 10 in theentrance side, is preferably in the range of 14-16 second. But, thewaiting time T1 may change depending on a number of rollers provided androtational speed of the motor, and the above waiting time T1 ispreferably well applied to the case that the heating roller 36 and thepressing roller 35 are provided in one pair, respectively.

Also, in case that the film is not detected by the film detecting sensor15 in the exit side at the step of detecting the film (step 108) and itis judged that the laminator does not normally operate, the roller isrotated backward for a predetermined period of time T2 so that the filmis removed from the inside of the laminator (step 110). For a method forrotating backward the roller, a method for rotating backward thedual-direction rotating motor is possibly used, and a variety of methodsfor mechanically reversing rotational direction using device may beadopted for a case of one direction rotating motor.

In the meantime, the time T2 for which the motor is rotated backward ispreferably in the range of 18-20 second. The time T2 for reverserotation of the motor is sufficient for removing the laminating film inthe jam status in the inside of the laminator or wound on the roller,and could change depending on rotational speed of the motor and a numberof rollers. Here, the time T2 for reverse rotation of the motor may bewell preferably used for the case that a pair of heating rollers 36 anda pair of pressing rollers 35 are adopted.

If the film is completely removed at the step of rotating backward themotor (step 110), the roller is rotated forward again so that newlaminating may be swiftly performed (step 111).

The reason why the heating roller 36 and the pressing roller 35 are notstopped during laminating job as described above, is for transformationnot to be generated to the rollers 35 and 36 by heat generated from theinside of the laminator when the rollers 35 and 36 are stopped.

In case that the rollers are rotated forward, the step of inserting thefilm (step 105) where new laminating film is inserted, is performed sothat the laminating job may be possibly performed again.

In case that the film detecting sensor 10 and 15 are provided in thefront and the back of the heating roller 36, detection of abnormaloperation of the laminator and removal of the film could be more swiftlyaccomplished.

The second embodiment of the method for controlling roller rotation ofthe laminator will be described in the following.

The second embodiment of the method for controlling roller rotation ofthe laminator are the same as the first embodiment except difference inthe procedure by which the film is removed from the inside of thelaminator. The step of removing the laminating film will be described indetail in the following.

A user could forcibly pull the film through the receiving member (referto reference numeral 5 in FIG. 1) during reverse rotation of the motorin the step of removing the laminating film (step 110 in FIG. 5). Inthat case, the film could be more swiftly and easily removed than thecase that the film is removed by reverse rotation of the motor. If thefilm is forcibly removed through the receiving member (refer toreference numeral 5 in FIG. 1) by external force of a user, then thefilm is not detected by the film detecting sensor 10 in the entranceside. Therefore, at the moment, the controlling substrate (refer toreference numeral 30 in FIG. 3) judges that the laminating film iscompletely removed from the receiving member 5, so that the rollers 35and 36 are rotated forward again even before a predetermined period oftime T2 lapses.

The foregoing second embodiment of the method for controlling rollerrotation of the laminator could remove the film that is not normallylaminated more swiftly and reliably, thereby improving speed of thelaminating process.

In the meantime, if the film is seriously wound on the roller, or is noteasily removed from the inside of the laminator, the rollers 35 and 36are continuously set to the position for reverse rotation by the powerswitch, whereby removal of the film could be reliably performed.

And, if the film is not removed in laminator during the determinedinterval, it may be possible to switch off the operation of the rollerand to switch off the heating of the heating roller, preventing the filmfrom melted adhesively in the laminator.

INDUSTRIAL APPLICABILITY

According to the apparatus and method for controlling roller rotation ofthe laminator of the present invention, the position of the film couldbe detected in the inside of the laminator, so that whether thelaminator normally operates or not could be swiftly known.

Also, a user could find out exactly and reliably the position of thefilm by electronically detecting method, not by feeling of a user,thereby preventing destruction of the laminator machine itself due towinding of the film on the roller for a long time.

Also, thanks to the construction that the sensors are provided in thefront and the back of the roller with respect to the progressingdirection of the laminating film, whether the film is wound on theroller or not is detected, whereby reliable operation of the productcould be guaranteed.

While the invention has been shown and described with reference tocertain preferred embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims.

1. An apparatus for controlling roller rotation of a laminatorcomprising: rollers installed in even numbers, for applying heat andpressure in order to perform coating using a laminating film; a filmdetecting sensor in an entrance side, formed in a front side or at leastone of said rollers with respect to the progressing direction of alaminating film, for detecting whether the laminating film is insertedor not; a film detecting sensor in an exit side, formed in a rear sideof at least one of said rollers for detecting whether the laminatingfilm is drawn out or not; a dual-direction rotating motor for rotatingthe roller forward or backward depending on a detecting signal from thefilm detecting sensors in the entrance side and the exit side; amicroprocessor for receiving a detecting signal from either or both ofsaid sensors and transmitting a controlling signal to the dual-directionrotating motor; and a power transferring unit for transferring powerfrom the dual-direction motor to the rollers.
 2. The apparatus accordingto claim 1, wherein the rollers are comprise a heating roller and apressing roller.
 3. The apparatus according to claim 1, wherein the filmdetecting sensor in the entrance side and/or the film detecting sensorin the exit side are/is an ultraviolet sensor whose light emitting unitand the light receiving unit are provided in one pair, for checkingwhether the laminating film is present or not by detecting lightreflected from the laminating film.
 4. The apparatus according to claim,further comprising: a temperature adjusting member formed on an outerperiphery of the laminator, for setting an appropriate temperaturedepending on each laminating film; a heat applying unit formed on anouter periphery, spaced from at least one roller, for applying heat onat least one roller according to designation by the temperatureadjusting member; and a temperature sensor formed on an outer peripheryof at least one roller, for checking whether the roller reaches anappropriate temperature.
 5. A method for controlling roller rotation ofa laminator comprising the steps of: counting time from the moment thatinsertion of a laminating film is detected by a film detecting sensor inan entrance side after the laminating film is inserted into thelaminator; detecting, at a film detecting sensor in an exit side, thelaminating film after a waiting time T1 that is necessary for normallaminating operation lapses; and if the laminating film is detectedbefore the waiting time T1 lapses, judging that normal laminating isperformed, and, if the laminating film is not detected even after thewaiting time T1 lapses, removing the film by rotating backward theroller for a predetermined period of time T2 for reversion rotationunder judgement that normal laminating is not preformed.
 6. The methodaccording to claim 5, wherein the waiting time T1 is within range of14-16 second.
 7. The method according to claim 5, wherein the time T2for reversion rotation is within a range of 18-20 second.
 8. The methodaccording to claim 5, wherein the rollers are automatically rotatedforward after the rollers are rotated backward for the time T2 forreverse rotation of the motor.
 9. The method according to claim 5,wherein in case that the film detecting sensor in the exit side and thefilm detecting sensor in the entrance side are provided in a front and aback of the heating roller, respectively, the waiting time T1 before thefilm is detected by the film detecting sensor in the exit side after thefilm is detected by the film detecting sensor in the entrance side, iswithin a range of 8-10 second.
 10. The method according to claim 5,wherein in case that the film detecting sensor in the exit side and thefilm detecting sensor in the entrance side are provided in a front and aback of the heating roller, the T2 for which the heating roller isrotating backward because the film is not detecting by the filmdetecting sensor in the exit side, is within a range of 9-10 second. 11.A method for controlling roller rotation of a laminator comprising thesteps of: counting time from the moment that insertion of a laminatingfilm is detected by a film detecting sensor in an entrance side afterthe laminating film is inserted into the laminator; detecting, at a filmdetecting sensor in an exit side, the laminating film after a waitingtime T1 that is necessary for normal laminating operation lapses; if thelaminating film is detecting before the waiting time T1 lapses, rotatingforward the rollers under judgment that normal laminating is performed,and if the laminating film is not detected even after the waiting timeT1 lapses, removing the film by applying external force and rotatingbackward under judgment that normal laminating is not performed, and ifthe laminating film is not detected by the film detecting sensor in theentrance side, rotating forward the rollers under judgement that thelaminating film is completely removed.
 12. The method according to claim11, wherein the waiting time T1 is within a range of 14-16 second. 13.The method according to claim 11, wherein the rotation of the rollerand/or heating of the heating roller is switched off, when the film isnot removed in laminator.
 14. An apparatus for controlling rollerrotation of a laminator comprising: at least one pair of rollersinstalled in even numbers, for applying heat and/or pressure in order toperform coating using a laminating film; a film detecting sensor in anentrance side, formed in a front side of a first roller with respect tothe progressing direction of the laminating film, for detecting whetherthe laminating film is inserted or not; a film detecting sensor in anexit side, formed in a rear side of a final roller, for detectingwhether the laminating film is drawn out or not; a microprocessor fordetecting a position of the laminating film by a detecting signal fromat least one of the sensors; and a motor and a power transferring unitfor rotating forward or backward the roller under control of themicroprocessor.
 15. An apparatus for controlling roller rotation of alaminator comprising: a heating roller installed in even numbers, forapplying heat in order to perform coating using a laminating film; afilm detecting sensor in an entrance side, formed in a front side of theheating roller with respect to the progressing direction of thelaminating film, for detecting whether the laminating film is insertedor not; a film detecting sensor in an exit side, formed in a rear sideof the heating roller, for detecting whether the laminating film isdrawn out or not; a microprocessor for receiving a detecting signal fromeither or both of the sensors and transmitting a controlling signal ofthe heating roller using the detecting signal; a dual-direction rotatingmotor for rotating the roller backward if the laminator does notnormally operate depending in a controlling signal from themicroprocessor, and a power transferring unit for transferring unit fortransferring power from the dual-direction motor to the roller.